Interconnected Nanosystems

ABSTRACT

Communication to or from a nanodevice is provided with a nanostructure-based antenna, preferably formed from, but not limited to, a single wall nanotube (SWNT). Other nanostructure-based antennas include double walled nanotubes, semiconducting nanowires, metal nanowires and the like. The use of a nanostructure-based antenna eliminates the need to provide a physical communicative connection to the nanodevice, while at the same time allowing communication between the nanodevice and other nanodevices or outside systems, i.e., systems larger than nanoscale such as those formed from semiconductor fabrication processes such as CMOS, GaAs, bipolar processes and the like.

CROSS-REFERENCE TO RELATED APPLICATIONS

The subject application is a continuation of U.S. application No.11/573,443 filed Jun. 10, 2009, which is a 371 application ofPCT/US2005/028893, filed Aug. 12, 2005, which claim the benefit of U.S.Provisional Application No. 60/601230, filed Aug. 12, 2004, whichapplications are incorporated by reference.

FIELD OF THE INVENTION

The present invention relates generally to the field of nanotechnology,and more particularly, to interconnects for nanotubes, nanowires andother nanoscale structures and devices.

BACKGROUND INFORMATION

Essentially all devices needed to make the equivalent of a moderndigital or analog circuit out of nanotubes and/or nanowires have beendemonstrated in prototype experiments, and elementary logic circuitshave been demonstrated. Various researchers have claimed thatnanowire/nanotube devices are superior to CMOS in various metrics, suchas transconductance per width or mobility. When properly phrased, theseclaims are true. The underlying, unspoken motivation remains, however,that the devices are or can be smaller than spatial resolution limitsposed by lithography, which would provide a route to extend Moore's lawinto the domain of nanotechnology.

The nanotube and nanowire devices developed to date have been contactedby lithographically fabricated electrodes. This is not a scalabletechnique for massively parallel processing, integrated nanosystems, dueto the geometrical limits of lithography. The potential high-densitycircuitry possible with nanowires and nanotubes will not be realized ifeach nanowire and nanotube is contacted lithographically.

Fault-tolerant architectural schemes have recently been proposed totackle this interconnect problem. For example, using N lithographicallyfabricated wires, it is possible to address individually 2^(N) nanowiresusing a binary-tree multiplexing scheme. Since the spacing between thenanowires is beyond the limits of lithography, the electricalconnections between the nanowires and lithographically fabricated wiresare random, but could in principle be measured after the manufacturingprocess. With this technique, each chip manufactured would have its ownunique firmware, specific to the nano-level physical hardware defects.

However, a more manufacturable interconnect is needed that allowsefficient implementation and full scalability of integrated nanosystems.

SUMMARY

Described below are exemplary embodiments of wireless interconnects fornanodevices and nanosystems. These embodiments are examples only and arenot intended to limit the invention.

The devices, systems and methods described herein provide wirelessinterconnects for nanodevices and nanosystems. More specifically,communication to or from a nanodevice is provided with ananostructure-based antenna, preferably formed from, but not limited to,a single wall nanotube (SWNT). Other nanostructure-based antenna includedouble walled nanotubes, semiconducting nanowires, metal nanowires andthe like. The use of a nanostructure-based antenna eliminates the needto provide a physical communicative connection to the nanodevice, whileat the same time allowing communication between the nanodevice and othernanodevices or outside systems.

In one embodiment, a wirelessly interconnected system includes ananodevice with a nanostructure-based antenna coupled thereto and anoutside system configured to communicate with the nanodevice using thenanostructure-based antenna. The nanodevice is configured to communicateover the nanostructure-based antenna.

In another embodiment, a method of fabricating an interconnectednanosystem includes forming a nanodevice having a communication lead andcoupling a nanostructure-based antenna to the communication lead.Preferably, the coupling of a nanostructure-based antenna to thecommunication lead comprises forming a carbon nanotube on the lead.

In yet another embodiment, a method of communicating with ananostructured device by wirelessly transmitting information from afirst device, and wirelessly receiving information at a second device,wherein at least one of the first and second devices is anano-structured device

In yet another embodiment, an interconnected system includes a firstdevice and a second device wirelessly coupled to the first device,wherein one of the first and second devices is a nanodevice.

In yet another embodiment, an interconnected system includes a firstdevice and a second device wirelessly coupled to the first device,wherein one of the first and second devices includes a nanostructure-based antenna.

The above and other preferred features, including various novel detailsof implementation and combination of elements will now be moreparticularly described with reference to the accompanying drawings andpointed out in the claims. It will be understood that the particularmethods and apparatus are shown by way of illustration only and not aslimitations. As will be understood by those skilled in the art, theprinciples and features explained herein may be employed in various andnumerous embodiments.

BRIEF DESCRIPTION OF THE FIGURES

The details of the invention, including fabrication, structure andoperation, may be gleaned in part by study of the accompanying figures,in which like reference numerals refer to like segments.

FIG. 1 depicts a schematic of one exemplary embodiment of anano-structure device.

FIG. 2 depicts a block diagram of one exemplary embodiment of aninterconnected nanosystem.

FIG. 3 depicts a block diagram of a carbon nanotube receiving antennaand dipole transmitting antenna.

FIG. 4 depicts a graph illustrating conductance measurements of thecarbon nanotube receiving antenna shown in FIG. 3.

It should be noted that the figures are not drawn to scale and thatelements of similar structures or functions are generally represented bylike reference numerals for illustrative purposes throughout thefigures. It also should be noted that the figures are only intended tofacilitate the description of the preferred embodiments.

DETAILED DESCRIPTION

Each of the additional features and teachings disclosed below may beutilized separately or in conjunction with other features and teachingsto provide wireless interconnects, such as nanostructure-based antennas,for nanodevices and nanosystems. Representative examples of the presentinvention, which examples utilize many of these additional features andteachings both separately and in combination, will now be described infurther detail with reference to the attached drawings. This detaileddescription is merely intended to teach a person of skill in the artfurther details for practicing preferred aspects of the presentteachings and is not intended to limit the scope of the invention.Therefore, combinations of features and steps disclosed in the followingdetail description may not be necessary to practice the invention in thebroadest sense, and are instead taught merely to particularly describerepresentative examples of the present teachings.

Moreover, the various features of the representative examples and thedependent claims may be combined in ways that are not specifically andexplicitly enumerated in order to provide additional useful embodimentsof the present teachings. In addition, it is expressly noted that allfeatures disclosed in the description and/or the claims are intended tobe disclosed separately and independently from each other for thepurpose of original disclosure, as well as for the purpose ofrestricting the claimed subject matter independent of the compositionsof the features in the embodiments and/or the claims. It is alsoexpressly noted that all value ranges or indications of groups ofentities disclose every possible intermediate value or intermediateentity for the purpose of original disclosure, as well as for thepurpose of restricting the claimed subject matter.

The disclosure provided herein relates to U.S. Provisional PatentApplication Ser. No. 60/601,230, filed on Aug. 12, 2004, whichapplication is incorporated herein by reference as if set forth in full.

The devices, systems and methods described herein provide wirelessinterconnects for nanodevices and nanosystems. More specifically,communication to or from a nanodevice is provided with ananostructure-based antenna, preferably formed from, but not limited to,a single wall nanotube (SWNT). Other nanostructure-based antenna includedouble walled nanotubes, semiconducting nanowires, metal nanowires andthe like. The use of a nanostructure-based antenna eliminates the needto provide a physical communicative connection to the nanodevice, whileat the same time allowing communication between the nanodevice and othernanodevices or outside systems, i.e., systems larger than nanoscale suchas those formed from semiconductor fabrication processes such as CMOS,GaAs, bipolar processes and the like.

Nanostructure-based antennas can be used for other antenna applicationsas well, including, but not limited to RFID applications. In some cases,each nanostructure, i.e., nanotube or nanowire, can be a separateantenna. In other cases, the nanostructure can be just part of anantenna. For example, nanotubes can be used as components of compositematerials wherein the nanotube-based composite material serves as theantenna.

FIG. 1 depicts an exemplary embodiment of a nanodevice 10 capable ofwireless communication. The nanodevice 10 has multiplenanostructure-based antennas 16, such as nanotube antennas, thattogether form antenna arrays 11 extending from each of the four sides ofthe nanodevice 10. Preferably, each nanotube antenna 16 within thearrays 11 has a separate resonant frequency and is configured tocommunicate over a separate wireless frequency channel corresponding tothat resonant frequency. In this manner, a multichannel communicationsignal transmitted from another device or outside system can be receivedby the nanodevice 10. Because each nanotube 16 within the array s 11receives information on a separate channel, each of the array 11 can actas a communication port where each antenna 16 effectively acts as aninput/output connection.

For instance, in this embodiment, the nanodevice 10 has fourteen circuitinputs 18 per device side, each connected to a separate nanotube antenna16. The input signals for each of these inputs 18 are transmitted fromanother device or outside system on fourteen separate channels so thateach nanostructure-based antenna 16 receives only the communicationstransmitted over the respective resonant frequency. This allows thetransfer of separate, unique amounts of information to each individualinput 18 via the respective nanostructure-based antennas 16.

The nanodevice 10 can have any number of nanotube antennas 16 configuredto receive, transmit or both. In embodiments where each nanotube antenna16 is tuned to a separate resonant frequency, the number of nanotubeantennas 16 available to receive data on separate channels is limitedonly by the available bandwidth.

The nanodevice 10 can be any nanoscale device, or device havingnanoscale components. The internal structure 12 of the nanodevice 10 canrange from simple nanotubes or nanoelectrodes to more complex integratednanosystems having nanotubes, nanowires, nanotransistors,self-assembling DNA and the like. Furthermore, the term nanoscale is notintended to limit the systems and methods herein but instead tofacilitate reference to any apparatus, structure, device, thing orobject measured with reference to nanometers. One of skill in the artwill readily recognize that the term nanoscale can include structuresthat are less than one nanometer in size, while also includingstructures that are greater than 1000 nanometers in size.

The nanostructure-based antennas 16 can be formed from any nanoscalestructure that acts as an antenna. In a preferred embodiment,nanostructure-based antennas 16 are formed from carbon single wallednanotubes (SWNTs). Each carbon SWNT antenna 16 can be tuned to aresonant frequency by adjustment of its length. For instance, a onecentimeter carbon SWNT antenna 16 has a resonant frequency of 4Gigahertz.

In a preferred embodiment, a carbon SWNT antenna is formed or grown, asdescribed in greater detail in copending application Ser. No.11/198,902, filed Aug. 4, 2005, entitled “SYNTHESIS OF SINGLE-WALLEDCARBON NANOTUBES” is incorporated herein by reference, in a singlefurnace system comprising a modified CVD reaction chamber which reducesthe turbulence of the gas flow of the hydrocarbon source provided duringthe growth phase. The reduced turbulence creates an enhanced environmentfor ultra-long nanotube formation. In addition, a raised platform,comprising an underlayer of metal, is deposited onto a substrate. Theraised platform allows the nanotube to grow freely suspended from thesubstrate in the low turbulence gas flow. This reduces any steric forceimpedance caused by the substrate and enables the nanotube to be grownto lengths on the order of centimeters.

FIG. 2 depicts an exemplary embodiment of an interconnected nanosystem100, including nanodevices 102 and an outside system 103. Here, eachnanodevice has multiple nanotube antennas 106 that together form ananotube antenna array 101. Preferably, each nanotube antenna 106 withinthe array 101 has a separate resonant frequency and is configured tocommunicate over a separate wireless frequency channel corresponding tothat resonant frequency. In this manner, a multichannel communicationsignal transmitted from outside the outside system 103 via an antenna107 can be received by the nanodevice 102. Because each nanotube 106within the array 101 receives information on a separate channel, array101 can act as a communication port where each antenna 106 effectivelyacts as an input/output connection.

For instance, in this embodiment each nanodevice 102 has four circuitinputs 108, each connected to a separate nanotube antenna 106. The inputsignals for each of these inputs 108 are transmitted from the outsidesystem 103 on four separate channels over communication path 104 so thateach nanostructure-based antenna 106 receives only the communicationstransmitted over the respective resonant frequency. This allows thetransfer of separate, unique amounts of information from the outsidesystem 103 to each individual input 108 via the respectivenanostructure-based antenna 106.

The interconnected nanosystem 100 is not limited to communication solelybetween the outside system 103 and a nanodevice 102. Each of thenanodevices 102 can communicate with other nanodevices 102 in a similarmanner over communication path 104.

Each nanodevice 102 can have any number of nanotube antennas 106configured to receive, transmit or both. In embodiments where eachnanotube antenna 106 is tuned to a separate resonant frequency, thenumber of nanotube antennas 106 available to receive data on separatechannels is limited only by the available bandwidth in communicationpath 104 or each individual channel. However, other techniques can beused to increase the data transferring capacity of system 100, such astime or code signal multiplexing and the like.

Antenna Experiment: As shown in FIG. 3, an unbalanced dipoletransmitting antenna, which is resonant at f=2.8 GHz, was placed about 2inches from a sample comprising a carbon nanotube receiving antenna withelectrode spacing of 200 micrometers. The nanotube antenna was formed inaccordance with the method described above.

In examining the nanotube receiving antenna, using a lock-in amplifier,the nanotube current was measured as a function of the RF radiationfield being ON or OFF and whether the field was applied at thetransmitting antenna's resonant frequency (fr=2.8 GHz) or not (f=1 GHz).The transmitting antenna was driven at a single frequency in CW modewith a power of +5 dBm by a network analyzer.

The measured data, shown in FIG. 4, indicates there is a 0.3millisiemens decrease in the nanotube's DC conductance when RF radiationat the resonant frequency of the transmitting antenna (f=2.8 GHz) wasapplied to the receiving nanotube antenna. When the transmitting antennais driven at a frequency far removed from its resonance, e.g. f=1 GHz,no change in the CNT's conductance was noticed, because the transmittingantenna efficiency was low. These results indicate that the CNT on thesample is acting as a receiving antenna.

In the foregoing specification, the invention has been described withreference to specific embodiments thereof. It will, however, be evidentthat various modifications and changes may be made thereto withoutdeparting from the broader spirit and scope of the invention. Forexample, each feature of one embodiment can be mixed and matched withother features shown in other embodiments. Features and processes knownto those of ordinary skill may similarly be incorporated as desired.Additionally and obviously, features may be added or subtracted asdesired. Accordingly, the invention is not to be restricted except inlight of the attached claims and their equivalents.

What is claimed is:
 1. A wirelessly interconnected system, comprising: ananodevice having at least one nanostructure-based antenna coupledthereto, wherein the nanodevice is configured to communicate over thenanostructure-based antenna.
 2. The system of claim 1, furthercomprising an outside system configured to communicate with thenanodevice using the nanostructure-based antenna.
 3. A method offabricating an interconnected nanosystem, comprising: forming ananodevice having at least one communication lead; and coupling ananostructure-based antenna to the communication lead.
 4. The method ofclaim 3, wherein coupling a nanostructure-based antenna to thecommunication lead comprises forming a carbon nanotube on the lead.
 5. Amethod of communicating with a nanostructured device comprising thesteps of wirelessly transmitting information from a first device, andwirelessly receiving information at a second device, wherein at leastone of the first and second devices is a nano-structured device.
 6. Themethod of claim 5 wherein the nano-structured device includes acommunication lead and a nano-structure-based antenna coupled to thecommunication lead.
 7. The method of claim 6 wherein thenano-structure-based antenna is a carbon nanotube.
 8. An interconnectedsystem, comprising: a first device, and a second device wirelesslycoupled to the first device, wherein one of the first and second devicesis a nanodevice.
 9. The system of claim 8 wherein the nanodevice havingat least one nanostructure-based antenna coupled thereto, wherein thenanodevice is configured to communicate over the nanostructure-basedantenna.
 10. The system of claim 9 wherein the nanostructure-basedantenna is a carbon single walled nanotube.
 11. The system of claim 9wherein the nanostructure-based antenna is a carbon double wallednanotube.
 12. The system of claim 9 wherein the nanostructure-basedantenna is a semi-conductor nanowire.
 13. The system of claim 9 whereinthe nanostructure-based antenna is a metal nanowire.
 14. The system ofclaim 8 wherein the nanodevice includes a plurality of communicationports and an array of nanostructure-based antennas coupled to theplurality of communication ports.
 15. The system of claim 14 wherein thearray of nanostructure-based antennas comprises an array of carbonsingle walled nanotubes.
 16. The system of claim 14 wherein the array ofnanostructure-based antennas comprises an array of carbon double wallednanotubes.
 17. The system of claim 14 wherein the array ofnanostructure-based antennas comprises an array of semi-conductornanowires.
 18. The system of claim 14 wherein the array ofnanostructure-based antennas comprises an array of metal nanowires.